221118822 has 80 divisors (see below), whose sum is σ = 513363312. Its totient is φ = 71383680.

The previous prime is 221118797. The next prime is 221118829. The reversal of 221118822 is 228811122.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a zygodrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221118829) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1613938 + ... + 1614074.

Almost surely, 2^221118822 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221118822, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (256681656).

221118822 is an abundant number, since it is smaller than the sum of its proper divisors (292244490).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

221118822 is an frugal number, since it uses more digits than its factorization.

221118822 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 207 (or 183 counting only the distinct ones).

The product of its digits is 1024, while the sum is 27.

The square root of 221118822 is about 14870.0646266249. The cubic root of 221118822 is about 604.7026948048.

Adding to 221118822 its reverse (228811122), we get a palindrome (449929944).

The spelling of 221118822 in words is "two hundred twenty-one million, one hundred eighteen thousand, eight hundred twenty-two".